Wearing a pink and green T-shirt, Anne Sims rode down Pennsylvania Avenue to the Capitol in her motorized scooter as her Alpha Kappa Alpha sisters marched with her.

Arthritis caused Sims, 70, to rely on the scooter to get around. But Sims said she was determined to march with her sorority sisters yesterday.

"I wouldn't miss it," said Sims, of Detroit, who pledged AKA in 1958 when she was a student at Wayne State University. "I'm so proud to be here with everyone."

Sorority leaders pegged the turnout at 30,000 people from nine predominantly black sororities and fraternities. They gathered yesterday at the National Council of Negro Women headquarters at Sixth Street and Pennsylvania Avenue NW and walked to the Capitol to call attention to the need for better education, health care and employment, particularly for African Americans.

The march was part of the weeklong AKA centennial convention, which ends today. Alpha Kappa Alpha, which has more than 200,000 members worldwide, is the nation's oldest African American sorority. The organization was founded at Howard University in 1908.

Many AKAs stay involved with the sorority long after their collegiate days, contributing their time to local and national projects.

Recent nationwide AKA initiatives included seminars on home ownership, computer training programs and house reconstruction projects in New Orleans and Mississippi after Hurricane Katrina. Its scholarship foundation gives out more than $130,000 every year.

Yesterday's six-block walk took a half-hour, and the women had fun along the way. "We're the soul-steppin' sorors of AKA," cheered Vernita Moses, 48 and Janet McGee, 50, of Michigan.

Nicole Sutherland-Hughes, 38, of Princeton, N.J., compared the march to the sorority's founding meeting. "This is a groundbreaking moment," she said.

At the Capitol, the marchers heard speeches from various members of Congress, including House Speaker Nancy Pelosi (D-Calif.) and House AKAs Sheila Jackson Lee (D-Tex.), Eddie Bernice Johnson (D-Tex.) and Diane E. Watson (D-Calif.).

Barbara McKinzie, AKA's national president, urged her sorority sisters and Congress to focus on issues involving health care and diseases and ailments that affect African Americans disproportionately, such as breast cancer, HIV, sickle cell disease, obesity and high blood pressure.

"We are leaders in our chosen fields," McKinzie said, "eager and able to give value [and] add to the quality of life for others."

As a sign of unity, the march was open to other fraternities and sororities, each donning its own colors: Alpha Phi Alpha, Delta Sigma Theta, Kappa Alpha Psi, Omega Psi Phi, Zeta Phi Beta, Phi Beta Sigma, Sigma Gamma Rho and Iota Phi Theta.

"Often when we join these groups, it's competitive, but here when we come together, it's a reminder of why we got started in the first place, to help our communities and for academic excellence," said AKA Linda Jaha, 50, of Oklahoma City.

With temperatures in the mid-90s, some women wore AKA-emblazoned visors and carried umbrellas as a shield against the sun. Others gathered around trees, occupying every patch of shade they could find. Organizers handed out bottles of water and set up a water-misting tent.

As the marchers walked down Pennsylvania Avenue, workers in buildings along the route waved and cheered them on.

By the time the three-hour ceremony ended, many had left early to seek shelter from the heat, but a few hundred stayed to the end.

Carolyn Bell, of Savannah, Ga., said she was inspired to continue her pledge of service through her sorority when she returns home. "Our work is not in a vacuum, but felt by the world and heard in the halls of Congress," she said.